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  1. Pouring LB Agar Plates

    Type
    Protocol
    ...maximum of ~100 colonies Pro-Tip If you will be screening a large number of colonies, we recommend using...
  2. Kit Free RNA Extraction

    Type
    Protocol
    ... Biology Reference Introduction This protocol describes how to extract RNA from tissues or cells without...
  3. Plasmids 101: Terminators and PolyA signals

    Type
    Blog Post
    ...initiation step of gene transcription; today we'll provide an overview on how transcription stops, or termination...from the transcription machinery. Terminators are found downstream of the gene to be transcribed, and typically...generally serves to promote transcript longevity in eukaryotes and promote transcript degradation in prokaryotes...thought to destabilize the transcription complex, initiating cleavage of the transcript.   Figure 1: ...expression levels. Transcription Termination Rho-dependent termination DNA transcription Polyadenylation...both prokaryotic and eukaryotic systems must be transcribed into RNA, which occurs in three phases: initiation...sequence-based element, is to define the end of a transcriptional unit (such as a gene) and initiate the process...
  4. New Optimized Genome-wide CRISPRko, CRISPRi, and CRISPRa Libraries

    Type
    Blog Post
    ...to conduct genome-wide gain of function screens. These screens can help reveal the function of lowly expressed...large-scale functional screens Read this blog post about genome-wide screening using CRISPR Resources...allowed scientists to easily perform genome-wide screens to effectively and efficiently investigate gene... per gene to increase confidence in the genetic screen. However, there are benefits to optimized libraries...resources and are particularly useful when trying to screen a limited number of cells like primary cells or... they conducted genome-wide negative selection screens with both A375 (melanoma) and AT29 (colon cancer...metrics to assess library performance in viability screens. Based on these metrics the Brunello library was...
  5. Plasmids 101: The Promoter Region – Let's Go!

    Type
    Blog Post
    ...initiating the transcription of your insert into RNA. In practice, the term "promoter" describes the combination...Promoter   Primarily used for RNA     transcript     Description Expression Additional considerations ...Primarily used for Description Expression Additional considerations T7 in vitro transcription/ general expression...for in vitro transcription, the promoter drives either the sense OR antisense transcript depending on ...controls the binding of the RNA polymerase and transcription factors, therefore promoters play a large role...
  6. New Tools Enable CRISPRa for Neuroscience Applications

    Type
    Blog Post
    ...engineered combinations of transcriptional activators to induce gene transcription at genomic sites targeted...found here. High-throughput screening strategies Although the tools described above make CRISPRa more accessible...subgenome-scale CRISPRa screening approach in embryonic stem (ES) cells to determine which transcription factors promote...this technological gap, a trio of recent papers describe the development of CRISPR activation (CRISPRa)...-optimized viral vectors, and high-throughput screening approaches. Here, we’ll highlight these recent...CRISPRa much simpler to implement in genome-wide screens over cDNA libraries. However, using CRISPRa to ...and RNA components, and several sgRNAs must be screened to identify effective ones. Simplified in vivo...
  7. Minigenomes - a Safe Way to Study Dangerous Viruses Like the Ebola Virus

    Type
    Blog Post
    ...gene transcription (6). The EBOV genome contains seven viral genes, each flanked by a transcription start...start signal sequence (gene start) and a transcription termination/polyadenylation signal sequence (gene...genome which are required for replication and transcription (Figure 1). All viral genes are removed and ...direct minigenome replication and reporter gene transcription by the EBOV polymerase (reviewed in 2, 5). The...minigenome is capable of being replicated and transcribed in the cell when the appropriate viral proteins...EBOV polymerase replicates the viral genome and transcribes viral genes. Four viral proteins are required...required for viral genome replication and transcription: NP, VP35, VP30, and L (reviewed in 5). The RNA genome...
  8. Rewiring Metabolic Circuitry with CRISPR RNA Scaffolds [Video]

    Type
    Blog Post
    ... to modulate dCas9 expression, multiple scRNA transcriptional programs can be regulated with dCas9 as ...for CRISPRi are described here: http://www.addgene.org/crispr/qi/ Plasmids described in  Zalatan et ...recent paper, "Engineering Complex Synthetic Transcriptional Programs with CRISPR RNA Scaffolds." Adam has...visualize the concepts discussed in the paper. The transcriptional control of multiple loci is deftly coordinated...CRISPR-based RNA scaffolds to mimic natural transcriptional programs on multiple genes. Modifying the ...synthetic RNA scaffolds that can recruit various transcriptional regulators (Zalatan et al. 2015).  These scaffolds...domains. Combined with dCas9, this new scaffold RNA (scRNA) will bind to a PAM-adjacent target nucleotide sequence...
  9. Plasmids 101: Repressible Promoters

    Type
    Blog Post
    ... polymerase and transcription factors. Since the promoter region drives transcription of a target gene...repressor then prevents transcription from occurring, which means that transcription is now OFF.   We’ll...other. For example, the GAL4 transcription factor cannot drive transcription from the QUAS promoter, and...and the QF transcription factor cannot drive transcription from the UAS promoter. This is important because...Repressible: An activator protein is bound, turning transcription ON. When a repressor binds the activator protein...cannot bind the promoter sequence anymore and transcription is turned OFF. Negative Repressible: A repressor..., but cannot bind the promoter sequence and transcription is ON. Once a co-repressor protein binds the...
  10. 28 Hot Plasmid Technologies from 2015

    Type
    Blog Post
    ...enhancement of transcriptional activation via binding of multiple copies of a transcription factor to a ...domain, which activates transcription of downstream genes. Nihongaki et al describe the targeted activation... to activate transcription. Chavez et al. 2015 extended upon these findings by screening for additional... mutagenized and screened for speed and voltage sensitivity. This hierarchical screen led to the generation...and downstream transcription activation or repression. The TCS light sensors described in ACS Synthetic...scientists have been successful in regulating gene transcription using DNA-guided optogenetic tools; however,...recognized by scFV antibodies fused to VP64 transcriptional activation domains. This system enabled the...
  11. Plasmids 101: Inducible Promoters

    Type
    Blog Post
    ... polymerase and transcription factors. Since the promoter region drives transcription of a target gene...promoter to induce transcription of the phage repressor cI. Repressor cI inhibits transcription from phage promoter... the promoter, turning it ON and initiating transcription.     Negative inducible In the OFF state, the...a bound repressor protein actively prevents transcription. Once an inducer binds the repressor protein...the DNA. With the repressor protein absent, transcription is turned ON. Types of inducible promoters Chemical...induction of a promoter. Below, you’ll find a short description of these three types of inducible promoters, ...removal of the lac repressor (lacI protein) for transcription to be activated. In the presence of lactose ...
  12. 27 Hot Plasmids from 2016

    Type
    Blog Post
    ...Receptor-ome Expression and Screening via Transcriptional Output-TANGO (PRESTO-TANGO) to screen the NCC-1 library...of a good screening experiment can be found on our blog post entitled “Genome-wide Screening Using CRISPR...an alternative method, called STARR-seq (self-transcribing active regulatory region sequencing) that tests...independently of their position relative to a transcription start site. In STARR-seq, randomly sheared genomic...contain an enhancer, it will activate its own transcription from the minimal promoter and its strength can...  CRISPR pooled libraries enable researchers to screen the entire genome for genes that regulate a wide...CRISPR knockout library and used this library to screen for genes involved in West Nile Virus (WNV) induced...
  13. CRISPR Activators: A Comparison Between dCas9-VP64, SAM, SunTag, VPR, and More!

    Type
    Blog Post
    ... a strong transcriptional activation domain. Guided by dCas9, VP64 recruits transcriptional machinery ...Mediator (SAM) Description SAM uses specially engineered sgRNAs to increase transcription. This is done...cells. VPR Description VPR fuses a tripartite complex with dCas9 to activate transcription. This complex...as two other potent transcriptional activators (p65 and Rta). These transcriptional activators work in ...interest. Upon binding, CRISPRa systems recruit transcription factors to increase gene expression. CRISPRa...CRISPRa methods vary in their transcriptional activators: some methods rely on fusion proteins while others...genes across diverse cell lines.   dCas9-VP64 Description CRISPR activation can occur through fusing dCas9...
  14. Multiplexed Overexpression of Regulatory Factors (MORF) collection

    Type
    Blog Post
    ...Transcription factors (TFs) act as the gate keepers for gene expression, turning transcription on and... regulatory network. The transcription atlas and library The transcription factor library The human... TFs is a useful finding. Transcriptional program changes from this screen successfully differentiated...-scale CRISPR Cas-9 knockout and transcriptional activation screening. Nat Protoc. 2017 (4):828-863. doi...approximately 1,800 TFs, with >3,500 unique isoforms transcribed from these sites. The Zhang lab generated a comprehensive...differentiation outcomes as well as global transcriptional changes. Using this road map, and what was ...from Joung et al.)    Putting MORF to work Screens and selections In its current format, the MORF ...
  15. Optogenetics + CRISPR, Using Light to Control Genome Editing

    Type
    Blog Post
    ...light-dependent activity to transcription, they fused BldD to the transcriptional activators p65 and VP64 ...readily found at Addgene. Shining light on transcriptional activation using dCas9 Initial photoactivatable...early 2015 focused on using light to control transcription. Two separate labs, Moritoshi Sato’s lab at ...photolyase homology region (CRY2PHR) fused to a transcriptional activator domain (VP64 or p65). Upon expression...the activator into position to activate gene transcription. The researchers tested a variety of combinations...CRY2FL-VP64, a fusion of full-length CRY2 and the transcriptional activator domain VP64. Using this system in...expresses the C-terminal fragment of Cas9 while transcription of the N-terminus is light-dependent (Yu et ...
  16. Plasmids 101: Using Transposons in the Lab

    Type
    Blog Post
    ...themselves as RNA transcripts and then rely on a reverse transcriptase enzyme to reverse transcribe back into ...they copy themselves as RNA transcripts and then use their reverse transcriptase (RT) enzyme to convert back...mutagenesis screens that detect loss-of-function or gain-of-function mutations. In these screens, the transposons...transposon for a mutagenesis screen. For example, piggyBac and Tol2 are best for screening promoters and enhancers...protein is either a transposase or a reverse transcriptase, depending on the mechanism of transposition...pol. The pol polyprotein encodes the reverse transcriptase and integrase enzymes which are required for...poly(A). ORF2 encodes endonuclease and reverse transcriptase activities.    Figure 1: Overview of...
Showing: 41 - 60 of 779 results